OpenAI o3 alternatives
9 models of comparable capability, ranked by blended token price. OpenAI o3 stays in the table, highlighted, as the baseline.
List prices checked
Ranked by blended token price
Cheapest first, at three input tokens per output token.
| # | Model | Provider | Input | Output | Blended | vs OpenAI o3 | Context |
|---|---|---|---|---|---|---|---|
| 1 | DeepSeek-V4-Pro | DeepSeek | $0.435 | $0.870 | $0.544 | 6.4× cheaper | 1M |
| 2 | Mistral Large | Mistral AI | $2.00 | $6.00 | $3.00 | 1.2× cheaper | 131K |
| 3 | GPT-5 | OpenAI | $1.25 | $10.00 | $3.44 | 1× dearer | 400K |
| 4 | Gemini 2.5 Pro | $1.25 | $10.00 | $3.44 | 1× dearer | 1M | |
| 5 | OpenAI o3you are here | OpenAI | $2.00 | $8.00 | $3.50 | — | 200K |
| 6 | Cohere Command A | Cohere | $2.50 | $10.00 | $4.38 | 1.3× dearer | 256K |
| 7 | Claude Sonnet 5 | Anthropic | $3.00 | $15.00 | $6.00 | 1.7× dearer | 200K |
| 8 | Grok 4 | xAI | $3.00 | $15.00 | $6.00 | 1.7× dearer | 256K |
| 9 | Claude Opus 5 | Anthropic | $5.00 | $25.00 | $10.00 | 2.5× dearer | 200K |
| 10 | Claude Fable 5 | Anthropic | $10.00 | $50.00 | $20.00 | 5× dearer | 200K |
Source: OpenAI pricing (May 2026). Published list prices only — committed-use discounts, regional variation, and per-request charges are not included. Not yet independently re-checked against the vendor’s page.
Questions
- What is the best alternative to OpenAI o3 in 2026?
- On blended token price, DeepSeek-V4-Pro is the cheapest comparable option — about 6.4× cheaper than OpenAI o3. Price is only half the decision: a model that costs 70% less but needs a second attempt on hard prompts is not a saving.
- Which alternative is cheapest for output-heavy work?
- Rank on the output column rather than the blended figure. Reasoning and agentic loops bill their thinking as output, so a model with cheap input and expensive output can end up the most costly option on the page despite looking competitive here.
- Do these alternatives have the same context window?
- No — the context column varies by more than 8× across this table. If you are feeding whole documents or codebases, filter on window size first and only then compare price, because a cheaper model that cannot hold your input is not an alternative at all.